Information is required to be transmitted at a high rate in a future mobile communication system, for example, the rate at which information is transmitted is up to 1 Giga bit per second (Gbit/s). Since a larger bandwidth and a higher carrier frequency have to be occupied for transmission of information at a high rate, only a hot spot can be covered due to a considerable path loss in some edge area of a cell, so transmission of information at a high rate can not be ensured in the edge area of the cell. In this case, high-rate information from a base station can be forwarded by means of the technology of Relay Node (RN) to thereby improve a coverage area of information transmission at a high rate from the base station. Apparently, the RN technology is an effective solution to a further extended coverage area of information transmission at a high rate and expanded capacity of a cellular system.
FIG. 1 is a schematic composition diagram of an existing mobile communication system with an RN.
Referring to FIG. 1, an information transmission link of the system illustrated in FIG. 1 is divided into two hops, i e., an access link and a backhaul link. The access link refers to a Transmission Time Interval (TTI) for transmission of information between an evolved Node B (eNB) and a User Equipment (UE) and a TTI for transmission of information between the RN and the UE. The backhaul link refers to a TTI for transmission of information between the eNB and the RN, where the information between the eNB and the RN and the information between the eNB and the UB can be transmitted in the same TTI.
FIG. 2 is a schematic structural diagram of an existing frame over a backhaul link of an RN.
In FIG. 2, the abscissa represents time and the ordinate represents frequency. In FIG. 2, a Transmit-Receive Guard (TRG) is a guard interval required by the RN from transmitting a signal to receiving a signal over the backhaul link, and the TRG occupies the 2nd, 3rd and 4th Orthogonal Frequency Division Multiplexing (OFDM) symbols of all the carriers; and a Receive-Transmit Guard (RTG) is a guard interval required by the RN from receiving a signal to transmitting a signal over the backhaul link, and the RTG occupies the 14th OFDM symbol period of all the carriers. The RN remains in a silent state over the access link, that is, it neither receives a data signal nor transmits a data signal, in a temporal range between the TRG and the RTG, i.e., in a short Cyclic Prefix (CP) backhaul link TTI or a short eNB-Relay TTI. Particularly, the RTG is necessary only for absolute synchronization between the RN and the eNB, and if no absolute synchronization is required between the RN and the eNB, the RTG may not be set in FIG. 2, that is, no guard interval is required to be set for the RN from receiving a signal to transmitting a signal over the backhaul link.
The RN receives a data signal and/or a control signal from the eNB after the end of the TRG and before the start of the RTG. A specific solution to how the RN can receive correctly a data signal and/or a control signal transmitted from the eNB has been absent so far in the prior art.